AT25DF641-S3H-T Atmel, AT25DF641-S3H-T Datasheet - Page 31

• Manufacturer Part Number: AT25DF641-S3H-T
• Description: IC FLASH 64MBIT 100MHZ 16SOIC
• Manufacturer: Atmel

Specifications of AT25DF641-S3H-T

• Format - Memory: FLASH
• Memory Type: DataFLASH
• Memory Size: 64M (32K pages x 256 bytes)
• Speed: 100MHz
• Interface: SPI, 3-Wire Serial
• Voltage - Supply: 2.7 V ~ 3.6 V
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 16-SOIC (0.300", 7.5mm Width)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

9.3.
9.4.
3680F–DFLASH–4/10
Read Sector Lockdown Registers
The Sector Lockdown Registers can be read to determine the current lockdown status of each physical 64-Kbyte
sector. To read the Sector Lockdown Register for a particular 64-Kbyte sector, the
and the opcode of 35h must be clocked in. Once the opcode has been clocked in, three address bytes
designating any address within the 64-Kbyte sector must be clocked in. After the address bytes have been
clocked in, data will be output on the SO pin during every subsequent clock cycle. The data being output will be a
repeating byte of either FFh or 00h to denote the value of the appropriate Sector Lockdown Register.
At clock frequencies above f
frequencies above f
correct status of the appropriate Sector Lockdown Register.
Table 9-3.
Deasserting the
pin can be deasserted at any time and does not require that a full byte of data be read.
Figure 9-3.
Program OTP Security Register
The device contains a specialized OTP (One-Time Programmable) Security Register that can be used for
purposes such as unique device serialization, system-level Electronic Serial Number (ESN) storage, locked key
storage, etc. The OTP Security Register is independent of the main Flash memory array and is comprised of a
total of 128-bytes of memory divided into two portions. The first 64-bytes (byte locations 0 through 63) of the OTP
Security Register are allocated as a one-time user-programmable space. Once these 64-bytes have been
programmed, they cannot be erased or reprogrammed. The remaining 64-bytes of the OTP Security Register
(byte locations 64 through 127) are factory programmed by Atmel and will contain a unique value for each device.
The factory programmed data is fixed and cannot be changed.
Output Data
SCK
SO
CS
SI
FFh
00h
Read Sector Lockdown Register – Output Data
Read Sector Lockdown Register
Sector Lockdown Register Value
Sector Lockdown Register value is 0 (sector is not locked down)
Sector Lockdown Register value is 1 (sector is permanently locked down)
CS
HIGH-IMPE DANC E
MS B
CLK
pin will terminate the read operation and put the SO pin into a high-impedance state. The
0
0
, at least two bytes of data must be clocked out from the device in order to determine the
0
1
1
2
OPC ODE
1
3
CLK
0
4
, the first byte of data output will not be valid. Therefore, if operating at clock
1
5
0
6
1
7
MS B
A
8
A
9
ADDR E S S BITS A23-A0
A
10 11
A
A
12
A
A
29 30
A
A
31 32
MS B
X
X
33
DON'T C AR E
X
34
X
35
X
36
X
37 38
Atmel AT25DF641
X
X
39
MS B
D
CS
40
D
41
pin must first be asserted
DATA BYTE
D
42 43
D
D
44
D
45
D
46
D
47 48
MS B
D
D
CS
31